archaeocerebellum

Greek archi = first, hence the oldest part of the cerebellum, which is the flocculonodular lobe.
Found on http://www.anatomy.usyd.edu.au/glossary/glossary.cgi?

archaeocerebellum

Synonym: archicerebellum. ... Origin: G. Archaios, ancient, + cerebellum ... (05 Mar 2000) ...
Found on http://www.encyclo.co.uk/local/20973

archaeocerebellum

Type: Term Pronunciation: ar′kē-ō-ser′ĕ-bel′lŭm Synonyms: archicerebellum
Found on http://www.medilexicon.com/medicaldictionary.php?t=6049
No exact match found